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Java printing database records on separate lines

I have a JDBC program that takes records from a MySQL database and prints out the results. The user can select which results they want from the database by selecting different checkboxes to only display certain results.
Here is the method which gets the records and prints them out:
private void execute() throws SQLException {
String query = "SELECT * FROM customers";
ResultSet rs = stmt.executeQuery(query);
String result = "";
while (rs.next()) {
if (cb1.isSelected()) {
int custid = rs.getInt("custid");
result += custid + " ";
}
if (cb2.isSelected()) {
String name = rs.getString("name");
result += name + " ";
}
if (cb3.isSelected()) {
String address = rs.getString("address");
result += address + " ";
}
if (cb4.isSelected()) {
String city = rs.getString("city");
result += city + " ";
}
if (cb5.isSelected()) {
String state = rs.getString("state");
result += state + " ";
}
if (cb6.isSelected()) {
int zip = rs.getInt("zip");
result += zip + " ";
}
// print the results
}
System.out.println(result);
results.setText(result);
stmt.close();
}
Currently, if I were to select say the first three checkboxes, I would get the output:
1 Smith, Tim 12 Elm St 2 Jones, Tom 435 Oak Dr 3 Avery, Bill 623 Ash Ave 4 Kerr, Debra 1573 Yew Crt
However, the output I am after is:
1, Smith, Tim, 12 Elm St
2, Jones, Tom, 435 Oak Dr
3, Avery, Bill, 623 Ash Ave
4, Kerr, Debra, 1573 Yew Crt
Is there any way I can add a new line after each record in the database, as well as maybe the commas in between items in each record? I am new to JDBC and MySQL connectivity, so any help or tips is appreciated.

You can print every single result just before the end of while loop, then it'll print every record in new line.
private void execute() throws SQLException {
String query = "SELECT * FROM customers";
ResultSet rs = stmt.executeQuery(query);
String result = "";
String singleResult = "";
while (rs.next()) {
if (cb1.isSelected()) {
int custid = rs.getInt("custid");
singleResult += custid + " ";
}
if (cb2.isSelected()) {
String name = rs.getString("name");
singleResult += name + " ";
}
if (cb3.isSelected()) {
String address = rs.getString("address");
singleResult += address + " ";
}
if (cb4.isSelected()) {
String city = rs.getString("city");
singleResult += city + " ";
}
if (cb5.isSelected()) {
String state = rs.getString("state");
singleResult += state + " ";
}
if (cb6.isSelected()) {
int zip = rs.getInt("zip");
singleResult += zip + " ";
}
System.out.println(singleResult);
result +=singleResult;
}
//System.out.println(result);
results.setText(result);
stmt.close();
}
Or you can append line separator, just before closing while loop
System.out.println(singleResult);
result +=singleResult;
result +="\n";

First, I would use a StringJoiner to gather the elements. Then, I would eliminate the many local temporary variables. Finally, I would use println in the loop and another StringJoiner for the final result. Like,
private void execute() throws SQLException {
String query = "SELECT * FROM customers";
ResultSet rs = stmt.executeQuery(query);
StringJoiner result = new StringJoiner(System.lineSeparator());
while (rs.next()) {
StringJoiner lineJoiner = new StringJoiner(", ");
if (cb1.isSelected()) {
lineJoiner.add(String.valueOf(rs.getInt("custid")));
}
if (cb2.isSelected()) {
lineJoiner.add(rs.getString("name"));
}
if (cb3.isSelected()) {
lineJoiner.add(rs.getString("address"));
}
if (cb4.isSelected()) {
lineJoiner.add(rs.getString("city"));
}
if (cb5.isSelected()) {
lineJoiner.add(rs.getString("state"));
}
if (cb6.isSelected()) {
lineJoiner.add(String.valueOf(rs.getInt("zip")));
}
System.out.println(lineJoiner);
result.add(lineJoiner.toString());
}
results.setText(result.toString());
stmt.close();
}
You could also do the same thing with Collection(s) like,
String query = "SELECT * FROM customers";
ResultSet rs = stmt.executeQuery(query);
List<String> msg = new ArrayList<>();
while (rs.next()) {
List<String> al = new ArrayList<>();
if (cb1.isSelected()) {
al.add(String.valueOf(rs.getInt("custid")));
}
if (cb2.isSelected()) {
al.add(rs.getString("name"));
}
if (cb3.isSelected()) {
al.add(rs.getString("address"));
}
if (cb4.isSelected()) {
al.add(rs.getString("city"));
}
if (cb5.isSelected()) {
al.add(rs.getString("state"));
}
if (cb6.isSelected()) {
al.add(String.valueOf(rs.getInt("zip")));
}
String line = al.stream().collect(Collectors.joining(", "));
System.out.println(line);
msg.add(line);
}
results.setText(msg.stream().collect(Collectors.joining(System.lineSeparator())));
stmt.close();
Prefer whichever you find most readable.

Best way to print data from two columns of mySQL database to jTextfield one after another

I am trying to make a program in which i read an input from the user i.e. in the textfield named gname and store its value to a string called grammar. Now this input is what sorts my output from the database.
Database looks like this
So when user enters G1 in the textfield it should display records in such a way
A->ab,A-ab,B->b
But it only shows 1st element when i use if(myRs.next) and last one if i use while(myRs.next().
current output is
Here is the code for this:
its all in try catch block
String grammar = gname.getText();
myCon = DriverManager.getConnection("jdbc:mysql://localhost:3306/grammar", "root", "");
JOptionPane.showMessageDialog(rootPane, "Connected to database");
mystmt = myCon.createStatement(
ResultSet.TYPE_SCROLL_SENSITIVE, ResultSet.CONCUR_UPDATABLE);
String query = "SELECT starting_symbol, value from starting_symbol where grammar= '" + grammar + "'";
String query2 = "SELECT non_terminals, terminals from input_values where grammar= '" + grammar + "'";
mystmt.addBatch(query);
mystmt.addBatch(query2);
myCon.setAutoCommit(false);
mystmt.addBatch(query);
mystmt.addBatch(query2);
myRs = mystmt.executeQuery(query);
while (myRs.next()) {
String s = myRs.getString("starting_symbol");
String val = myRs.getString("value");
output.setText(s + "-> " + val);
}
myRs = mystmt.executeQuery(query2);
ArrayList<String> list_one = new ArrayList<String>();
ArrayList<String> list_two = new ArrayList<String>();
while (myRs.next()) {
list_one.add(myRs.getString("non_terminals"));
list_two.add(myRs.getString("terminals"));
for (int i = 0; i < list_one.size(); i++) {
output_2.setText(list_one.get(i) + "->" + list_two.get(i));
}
}
Please help me in getting the correct outut

Use StringBuilder Luke
StringBuilder b = new StringBuilder();
while (myRs.next()) {
String s = myRs.getString("starting_symbol");
String val = myRs.getString("value");
if (b.length() > 0) {
b.append(',');
}
b.append(s + "-> " + val);
}
output.setText(b.toString());
And do the same for output_2 field

Your code snippet can be just like the following:
StringBuilder sb = new StringBuilder();
while (myRs.next()) {
if (sb.length() > 0) sb.append(",");
sb.append(myRs.getString("non_terminals"))
.append("->")
.append(myRs.getString("terminals"));
}
Instead of calling output_2.setText multiple times that only set the text to be the last fetch value of non_terminals -> terminals in this case B->b.

How to customize the TotalRecordCount and Paging after filter in jTable jquery (Java-JSP)

I use a jTable jquery for jsp page, it work very well. It can display the showing count records in bottom right of table well (e.g. Showing 1-10 of 22). When I insert the Filtering into the page, the showing count record is not correctly.
I follow this for Filtering: http://www.jtable.org/Demo/Filtering
How to customize the code for showing count record (I use java-jsp and sql server). Sorry for my English language :))
Here is the code I am using right now in controller.
if (action.equals("list")) {
try {
int startPageIndex = Integer.parseInt(request.getParameter("jtStartIndex"));
int numRecordsPerPage = Integer.parseInt(request.getParameter("jtPageSize"));
String jtSorting = null;
//Fetch Data from Rejected_Product Table
lstSite = dao.**getAllSite**(filter_site, startPageIndex, numRecordsPerPage, jtSorting);
//Get Total Record Count for Pagination
int siteCount = dao.**getSiteCount**();
//Convert Java Object to Json
Gson gson = new Gson();
JsonElement element = gson.toJsonTree(lstSite, new TypeToken<List<Site>>() {
}.getType());
JsonArray jsonArray = element.getAsJsonArray();
String listData = jsonArray.toString();
//Return Json in the format required by jTable plugin
listData = "{\"Result\":\"OK\",\"Records\":"+listData+",\"TotalRecordCount\":"+siteCount+"}";
response.getWriter().print(listData);
System.out.println(listData);
} catch (Exception ex) {
String error = "{\"Result\":\"ERROR\",\"Message\":" + ex.getStackTrace() + "}";
response.getWriter().print(error);
ex.printStackTrace();
}
}
and here method getAllSite:
public List<Site> getAllSite (FilterSite filter_site, int jtStartIndex, int jtPageSize, String jtSorting) {
List<Site> siteList = new ArrayList<Site>();
String query = "";
String siteQ = filter_site.getSite();
String clientQ = filter_site.getClient(); // wait
String locationQ = filter_site.getLocation();
if (locationQ.isEmpty()) {
locationQ = "";
} else {
locationQ = "and location like '%"+locationQ+"' ";
}
String site_idQ = filter_site.getSite_id();
if (site_idQ.isEmpty()) {
site_idQ = "";
} else {
site_idQ = "and site_id = '"+site_idQ+"' ";
}
String divisionQ = filter_site.getDivision();
if (divisionQ.isEmpty()) {
divisionQ = "";
} else {
divisionQ = "and division = '"+divisionQ+"' ";
}
int range = jtStartIndex+jtPageSize;
query = "SELECT * FROM (SELECT *, ROW_NUMBER() OVER (ORDER BY CODE) as row FROM [site]) a "
+ "WHERE (code like '%"+siteQ+"' "+locationQ+site_idQ+divisionQ+") "
+ "and row > "+jtStartIndex+" and row <= "+range;
try {
Statement statement = connection.createStatement();
ResultSet rs = statement.executeQuery(query);
System.out.println("query : "+query);
while (rs.next()) {
Site sitebean = new Site();
sitebean.setName(rs.getString("name"));
sitebean.setCode(rs.getString("code"));
.....
siteList.add(sitebean);
}
} catch (SQLException e) {
e.printStackTrace();
}
return siteList;
}
and here method getSiteCount :
public int getSiteCount () {
int count = 0;
String query = "SELECT COUNT(*) as count FROM [site] ";
try {
Statement statement = connection.createStatement();
ResultSet rs = statement.executeQuery(query);
while (rs.next()) {
count = rs.getInt("count");
}
} catch (SQLException e) {
e.printStackTrace();
}
return count;
}

If you mean by "not correctly" that the row count is larger than expected, then the solution would be to include the where clause in the siteCount query.
WHERE (code like '%"+siteQ+"' "+locationQ+site_idQ+divisionQ+")

Search a JTable using multiple JTextfield

I have a JFrame that has 3 JTextfields and 2 JDatechooser, what I am trying to do is if only one JTextfield has something typed in it and I press the search button, then I will be able to retrieve the data to JTable, but the problem is I have to fill out all JTextFileds and JDatechooser in order to retrieve data. My idea is to ignore null JTextfields and JTdatechooser if only one JTextfield has the keyword I want ?? Any suggestions ?? Thanks in advance,
public ArrayList<BillsRecord> getBillRecordByID(int EmpCode, String Fname, String Lname, String sDate, String eDate) throws SQLException {
String sql = "SELECT B.DATE AS DT, B.EMP_ID, E.FNAME, E.LNAME, MONEY_SENT, RENT, PHONE, GAS, ELECTRICITY, INTERNET, OTHER"
+ " FROM EMPLOYEE E INNER JOIN BILLS B ON E.EMP_ID = B.EMP_ID"
+ " WHERE B.EMP_ID = ? "
+ " OR E.FNAME = ? "
+ " OR E.LNAME = ? "
+ " OR DATE BETWEEN ? AND ? "
+ " ORDER BY B.DATE";
DBConnection con = new DBConnection();
Connection connect = con.getConnection();
PreparedStatement ps = null;
ArrayList<BillsRecord> records = new ArrayList<>();
try {
ps = connect.prepareStatement(sql);
ps.setInt(1, EmpCode);
ps.setString(2, Fname);
ps.setString(3, Lname);
ps.setString(4, sDate);
ps.setString(5, eDate);
ResultSet rs = ps.executeQuery();
if (rs.next()) {
BillsRecord billrec = new BillsRecord();
billrec.setDATE(rs.getString("DT"));
billrec.setEMP_ID(rs.getInt("EMP_ID"));
billrec.setFNAME(rs.getString("FNAME"));
billrec.setLNAME(rs.getString("LNAME"));
billrec.setMONEY_SENT(rs.getDouble("MONEY_SENT"));
billrec.setRENT(rs.getDouble("RENT"));
billrec.setPHONE(rs.getDouble("PHONE"));
billrec.setGAS(rs.getDouble("GAS"));
billrec.setELECTRICITY(rs.getDouble("ELECTRICITY"));
billrec.setINTERNET(rs.getDouble("INTERNET"));
billrec.setOTHER(rs.getDouble("OTHER"));
records.add(billrec);
return records;
}
} catch (SQLException e) {
System.out.println(e.toString());
} finally {
if (ps != null) {
ps.close();
}
if (connect != null) {
connect.close();
}
}
return null;
}
private void search() {
try {
JTextField stxt = ((JTextField) startdatetxt.getDateEditor().getUiComponent());
String sDATE = stxt.getText().trim();
JTextField etxt = ((JTextField) enddatetxt.getDateEditor().getUiComponent());
String eDATE = etxt.getText().trim();
int EMP_ID = Integer.parseInt(this.empidtxt.getText().trim());
String FNAME = this.firstnametxt.getText().trim();
String LNAME = this.lastnametxt.getText().trim();
BillRecordDao billrecdao = new BillRecordDao();
ArrayList<BillsRecord> records = billrecdao.getBillRecordByID(EMP_ID, FNAME, LNAME, sDATE, eDATE);
Object[] tableColumnName = new Object[11];
tableColumnName[0] = "Date";
tableColumnName[1] = "H.License";
tableColumnName[2] = "First Name";
tableColumnName[3] = "Last Name";
tableColumnName[4] = "MONEY SENT";
tableColumnName[5] = "RENT";
tableColumnName[6] = "PHONE";
tableColumnName[7] = "GASE";
tableColumnName[8] = "ELECTRICITY";
tableColumnName[9] = "INTERNET";
tableColumnName[10] = "OTHER";
DefaultTableModel tbd = new DefaultTableModel();
tbd.setColumnIdentifiers(tableColumnName);
this.BillsSummaryTable.setModel(tbd);
Object[] RowRec = new Object[11];
for (int i = 0; i < records.size(); i++) {
RowRec[0] = records.get(i).getDATE();
RowRec[1] = records.get(i).getEMP_ID();
RowRec[2] = records.get(i).getFNAME().toUpperCase();
RowRec[3] = records.get(i).getLNAME().toUpperCase();
RowRec[4] = records.get(i).getMONEY_SENT();
RowRec[5] = records.get(i).getRENT();
RowRec[6] = records.get(i).getPHONE();
RowRec[7] = records.get(i).getGAS();
RowRec[8] = records.get(i).getELECTRICITY();
RowRec[9] = records.get(i).getINTERNET();
RowRec[10] = records.get(i).getOTHER();
tbd.addRow(RowRec);
}
} catch (SQLException e) {
System.out.println(e.toString());
}
}

Basically, you need to create a variable/dynamic query based on the available values
Now, you can do this using something like StringBuilder or even storing each query element in a List or array, but you always end up with the "trailing OR" problem (you need to know when you've got to the last element and not append the "OR" to the String or remove the trailing "OR" from the resulting String). While not difficult, it's just a pain.
However, if you're using Java 8, you can use StringJoiner!
StringJoiner sj = new StringJoiner(" OR ");
String sql = "SELECT B.DATE AS DT, B.EMP_ID, E.FNAME, E.LNAME, MONEY_SENT, RENT, PHONE, GAS, ELECTRICITY, INTERNET, OTHER"
+ " FROM EMPLOYEE E INNER JOIN BILLS B ON E.EMP_ID = B.EMP_ID"
+ " WHERE ";
List values = new ArrayList();
// EmpCode MUST be a Integer, so it can be null
if (EmpCode != null) {
sj.add("B.EMP_ID = ?");
values.add(EmpCode);
}
if (FName != null) {
sj.add("E.FNAME = ?");
values.add(FName);
}
if (LName != null) {
sj.add("E.LNAME = ?");
values.add(LName);
}
if (sDate != null && eDate != null) {
sj.add("DATE BETWEEN ? AND ?");
values.add(sDate);
values.add(eDate);
}
sql += sj.toString();
Connection connect = null;
try (PreparedStatement ps = connect.prepareStatement(sql)) {
for (int index = 0; index < values.size(); index++) {
ps.setObject(index + 1, values.get(index));
}
try (ResultSet rs = ps.executeQuery()) {
if (rs.next()) {
//...
}
}
} catch (SQLException exp) {
exp.printStackTrace();
}
You might also like to have a look at The try-with-resources Statement and have a read through Code Conventions for the Java TM Programming Language, it will make it easier for people to read your code and for you to read others

Executing SQL Statement by getting Boolean Java

I have 2 Frames let's name them "Request" and "Confirm". Now when clicking a Button in "Request" the Frame "Confirm" is called. And when clicking "yes" a SQL Statement should be executed. The thing is that the SQL Statement is in class "Request". The Class "Confirm" should be called from other Frames too, so I don't want to make an Action Listener on the Button "yes" in "Confirm". I what to get a boolen by clicking the "yes" Button. If its true the statement in 'Request" should be executed.
How I can do this?
ReqBnt.addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent arg0) {
if (arg0.getSource() == ReqBnt) {
String VendN = txtVendN.getText();
String VendSN = txtVendSN.getText();
String Ad = txtAd.getText();
String Ads = txtAds.getText();
String City = txtCity.getText();
String Zip = txtZip.getText();
String UID = txtUID.getText();
String Reg = txtReg.getText();
String Rep = txtRep.getText();
String Tel = txtTel.getText();
String Fax = txtFax.getText();
String Mail = txtMail.getText();
String Iban = txtIban.getText();
String Bic = txtBic.getText();
String BInst = txtBInst.getText();
String VendInfo = txtVendInfo.getText();
String Flag = "Y";
String PT = comboPT.getSelectedItem().toString();
String Ctry = comboCtry.getSelectedItem().toString();
try{
try {
String sqlx = "SELECT `Abbreviation 2`, `Country English` From `database`.`country_master` " +
"WHERE `Country English` = '" + Ctry + "'";
PreparedStatement pstx = conn.prepareStatement(sqlx);
ResultSet rs = pstx.executeQuery();
while (rs.next()){
partCode = rs.getString("Abbreviation 2");
}}catch (Exception ex) {
System.out.println("Abbreviation Not Found");
}
String sqlFind = "Select max(substring(`Vendor Code`, 3)) From `database`.`vendor_master`";
try {
PreparedStatement pstFind = conn.prepareStatement(sqlFind);
ResultSet rs = pstFind.executeQuery();
while (rs.next()){
partNo = rs.getInt("Vendor Code")+1;
}}catch (Exception ex) {
partNo = 10001;
}
String VendC = partCode+partNo;
try {
String sqlx = "SELECT `Abbreviation Use`, `Country English` From `database`.`country_master` " +
"WHERE `Country English` = '" + Ctry + "'";
PreparedStatement pstx = conn.prepareStatement(sqlx);
ResultSet rs = pstx.executeQuery();
while (rs.next()){
CtryC = rs.getString("Abbreviation Use");
}}catch (Exception ex) {
System.out.println("Abbreviation Not Found");
}
Calendar currentDate = Calendar.getInstance(); //Get the current date
SimpleDateFormat formatter= new SimpleDateFormat("dd.MM.yyyy HH:mm:ss");
String dateNow = formatter.format(currentDate.getTime());
//if
// 1.step: check if there are null values
// 2.step: if there are no null values -> call frame "Confirm"
// 3.step: if Confirm = true -> execute statement
// if Confitm = fals -> do nothing
try {
String sql = "INSERT INTO `database`.`vendor_master`(`Vendor Code`,`Vendor Full Name`,`Vendor Short Name`,"+
"`Address`,`Address Suffix`,`ZIP Code`,`City`,`Country`,`Country Code`,`UID No`,`Registration No`,"+
"`Payment Term`,`Creation Date`,`IBAN`,`BIC`,`Banking Institution`,`Representive`,`Email Address`,"+
"`Telefon No`,`Fax`,`Vendor Information`,`Active Flag`) "+
"Values('"+VendC+"','"+VendN+"','"+VendSN+"','"+Ad+"','"+Ads+"','"+Zip+"','"+City+"','"+Ctry+"','"+CtryC+"','"+
UID+"','"+Reg+"','"+PT+"','"+dateNow+"','"+Iban+"','"+Bic+"','"+BInst+"','"+Rep+"','"+Mail+"','"+Tel+"','"+
Fax+"','"+VendInfo+"','"+Flag+"')";
PreparedStatement pstExecute = conn.prepareStatement(sql);
pstExecute.execute();
System.out.println("Vendor Registered");
}catch (Exception ex) {
System.out.println("Please insert required Fields!");
}
///end if
}catch (Exception ex) {
System.out.println("Error: "+ex);
}
}
}
});

Try using a JDialog instead:
int dialogResult = JOptionPane.showConfirmDialog (
null,
"Are you sure you want to do that?",
"Warning",
JOptionPane.YES_NO_OPTION);
if(dialogResult == JOptionPane.YES_OPTION){
//Do a thing here
}
You can Take a look at the dialog here:
http://docs.oracle.com/javase/tutorial/uiswing/components/dialog.html
You can even extend JDialog instead if you want more functionality.